Problem: $f(n)=-11+22(n-1)$ Complete the recursive formula of $f(n)$. $f(1)=$
Answer: From the explicit formula, ${-11}+{22}(n-1)$, we can tell that the first term of the sequence is ${-11}$ and the common difference is ${22}$. This is the recursive formula of the sequence: $\begin{cases} f(1)={-11} \\\\ f(n)=f(n-1)+{22} \end{cases}$